Intake And Exhaust Manifolds; Camshaft; Camshaft Bearings; Timing Chain And Sprockets - Chevrolet 1988 Light Duty Truck Repair Manual

M easu re
Piston pin diam eter and clearance.
Piston to bore clearance, and fit pistons as outlined.
A ssem b le
Com ponents as outlined.
Im p o rta n t
• Each connecting rod and bearing cap should
be m arked, b e g in n in g at the front of the
engine. Cylinders 1, 3 and 5 are at the left
bank, and 2, 4 and 6 are the right bank. The
num bers on the connecting rod and bearing
cap must be on the same side when installed
in the cylinder bore. If a connecting rod is ever
transposed from block or cylinder to another,
new connecting rod bearings should be fitted
and the connecting rod should be numbered
to correspond with the new cylinder number.
M easu re
• Ring end gap and ring clearance.
IV
In sp ect
• Ring fit.
INTAKE AND EXHAUST
MANIFOLDS
iff
Clean
Old pieces of gasket from the gasket surfaces.
Excessive carbon build-up in the exhaust passages
of the intake manifold.
Scale and deposits from the coolant passages of the
intake manifold.
EGR passage of excessive carbon deposits.
In sp ect (F ig u re 14)
M anifolds for cracks, broken flanges, and gasket
surface damage.
4.3 LITER V
A lignm ent of m anifold flanges. Use a straight edge
and feeler gage. If the flanges do not align, the
manifold is warped and should be replaced.

CAMSHAFT

Im p o rtan t
W henever the cam shaft needs to be replaced, a
new set of lifters must also be installed.
Inspect
Cam shaft lobes and journals for scratches, pitting,
scoring, and wear.
m
M easu re
Cam shaft journal diam eter (figure 15). The proper
diam eter is listed in " S pecifications."

CAMSHAFT BEARINGS

Refer to GENERAL ENGINE MECHANICAL (SEC. 6A)
for replacem ent procedures.

TIMING CHAIN AND SPROCKETS

I ? Inspect
• Sprockets for chipped teeth and wear.
• Tim ing chain for damage.
• It should be noted that excessively worn sprockets
w ill ra p id ly w e a r a new c h a in . L ik e w is e , an
excessively worn chain will rapidly wear a new set of
sprockets.
CRANKSHAFT SPROCKET REPLACEMENT
R em o ve or D isco n n ect (F ig u re 16)
Tool Required:
J 5825-A Crankshaft Sprocket Puller
1. Crankshaft sprocket using J 5825-A.
2. Key (if necessary).
6A3-11
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